The demonstration marks the United Nations' recognised day of international commemoration of the suffering and killing of millions of animals in labs across the world.
Campaigners from around the UK gathered in Hyde Park for anti-vivisection speeches before they began their march through London.
Organisers expected it to be the biggest animal rights demonstration for years. Campaigners say that in the 10 years since Labour came to power, the Government has done little to carry out pre-election promises regarding animal experiments.
V E R OVOICE FOR ETHICAL RESEARCH AT OXFORD
UPDATE April 2009 JOIN THE MAKE ANIMAL TESTING HISTORY VIRTUAL MARCH!
Join the virtual march to Brussels and become one of thousands of citizens across Europe supporting the Make Animal Testing History campaign.
Sign the pledge of support, then create your own avatar figure and get marching!
Launched by the Dr Hadwen Trust, Four Paws and the Humane Society International and supported by various groups including VERO.